Metallurgical furnace.



mouth or spout 5 of STATES PATENT OFFICE.

WILLIAM BUHL, OF CARNEGIE, PENNSYLVANIA.

METALLURGICAL FURNACE.

' Specification of Letters Patent.

Patented Jan. 22, 1918.

Application filed August 20, 1917. Serial No. 187,238.

To all whom it may concern:

Be it known that I, WILLIAM BUHL, a

citizen of the United States, and resident of furnace, and particularly to a furnace of the electric type.

In electric furnaces in which electrodes projecting through the furnace roof are employed in forming the heatlng arc, 1t has heretofore been necessary to introduce the metal to be treated through small doors in the bowl of the furnace. This fact has caused the operation of charging the furnace to be necessarily slow, and has also resulted in an inconvenient loss of time in cooling the furnace when repairs to the lining of the furnace bowl have become necessary.

The object of the present invention is to provide means whereby-the entire roof of an electric or other metallurgical furnace may be readily moved to one side thereof to uncover the furnace bowl either partially or completely, in order to permit a ready charging or rapid cooling of the same. A further object of the invention is to provide means for effecting such purpose which are readily adapted to use with the well known Heroult type of tiltin electric furnace, and which comprise modi cations which may be economically and readly made therein without altering the general construction of the furnace as a whole or interfering with its tilting. feature.

In the accompanying drawings Figure l is a view partly in vertical section and partly in side elevation of the apparatus-of the present invention applied to an electric furnace of the Heroult'type; and Fig. 2 is a rear elevation of a similar furnace, indicating in dotted lines the position taken by the roof and its supporting means when so moved as to uncover the furnace bowl.

The furnace bowl 1 is shown formed, as is usual, of an exterior metal shell and an interior refractory lining. This bowl is supported on suitable cross beams 2 over a plt 3 containing suitable tiltlng mechanism, and is pivoted on a trunnion L adjacent the the furnace. The furnace roof 6, arranged to rest on the bowl 1, is provided with suitable apertures through which project electrodes 7 of any suitable material, carbon electrodes being those preferably used with the type of furnace shown.

The electrodes 7 are supported in suitable electrode holders carried by brackets 8. These brackets are arranged to be vertically adjustable on suitable structural frame work or masts 9 located immediately to the, rear of the furnace bowl 1. The above description applies to a Heroult furnace of the usual and commercial form. In such furnaces however, the structural work or masts 9 are immovable relatively to the furnace bowl, and the furnace roof is not so secured to the masts that it may be wholly supported thereby.

The furnace roof as shown is secured to the masts 9, as by means of the bolts 10 and stays 11; and, while it may normally be permitted to rest upon the bowl 1 of the furnace, is formed completely independent thereof. The electrode brackets 8 are vertically movable in the masts by means of cables 12, passing over sheaves 13 at the upper extremities of the masts, and around suitable winding drums 14. The drums 14 may be actuated by any suitable form of motor which may be connected to a regulator, such as the Thury regulator, for causing slight automatic adjustment of the elec: trodes during the treatment of a charge, such regulator being cut out when it is desired to raise the electrodes any considerable distance on the masts 9. The masts 9 are of such height that when the electrode brackets 8 are raised to their extreme upward position by these means, the lower extremities of the electrodes 7 will be raised above the upper extremity of the bowl 1 without disturbing the position of the electrodes themselves in the electrode holders.

Adjacent the furnace bowl, and extending any desired distance therebeyond, are disposed vertically inclined ways shown as formed of a T-rail 15 and thrust rail 16. The vertical masts 9 are rigidly secured at their lower extremities to a truck 17 arranged to run on these inclined ways. The masts are so disposed relatively to this truck that they are perpendicular with the ground line and are therefore at an angle to the truck itself. When, therefore, the truck is caused to progress along the ways in a ,direction toward the left in Fig. 2, the roof 6, rigidly secured to the masts, will be simultaneously raised vertically from the furnace bowl carried as far as desired therebeyond. It will be understood that the object" of the inclination of the ways adjacent the furnace is to secure this vertical movement of the roof for lifting it clear of the furnace bowl, in case it may be permitted to rest thereon for greater convenience during the treatment of a charge in the furnace. If then some mechanical equivalent be employed to produce this vertical movement, or if it be rendered unnecessary by normally suspending the roof 6 free of the bowl, the tracks may be made horizontal throughout their length and the masts set perpendicularly to the truck 17. The movement of the truck and masts may be accomplished by any suitable means or agency, an axle motor 18 being indicated as one means of locomotion. lhe entire mast structure is so spaced and secured to the bowl of the furnace that it will be held securely in position thereagainst during the tilting of the furnace. Suitable means for'accomplishing this purpose are shown as angle irons or beams 12 secured to the furnace bowl, and to which the masts may be secured by any suitable means such as the swing bolts20.

lVith the furnace in charged or operative position, as shown in Fig. l of the drawings, the roof 6 rests on the bowl 1 of the furnace, and the structural work or masts 9 are secured to the furnace bowl. In this position of the parts, accidental movement of the truck relative to the furnace is prevented, and the entire truck'and mast apparatus will tilt readily with the furnace on the beams 2 during the pouring or teeming of a heat. lVhen it is desired to remove the roof 6 for charging the furnace or making repairs to the lining of the bowl, or other part of the furnace, the connection between the masts 9 and the bowl of the furnace is broken, and the masts and roof are moved into the position indicated in dotted lines in Fig. 2. To bring the partsinto this position the swing bolts 20 are disengaged, and the electrode carrying brackets 8 are moved to their uppermost position, so that the electrodes are raised clear of the furnace bowl.

The truck 17 is then progressed along the inclined ways, and this movement, owing to the rigid attachment ofthe roof 6 to the masts, will cause the roof to be raised from its position of rest on the bowl 1 and carried into the position indicated in dotted lines in Fig. 2. It will be understood that movement of the truck in the opposite direction will cause the roof to be carried back and lowered into position on the furnace bowl.

It will be apparent that in this position the furnace may be quickly charged with metal from any efficient charging means, so that the time required to charge the furnace may obviously be materially reduced over that required in charging the furnace through the relatively small doors usually provided. A furnace of the type shown will,

with its roof removed, also cool in a much shorter time than when the roof is allowed to remain in position and the doors only are opened; this rapidity of cooling resulting in a great saving of time when it is neces sary for workmen to enter the interior of the furnace bowl in order to repair its lining. In addition to the above advantages, the ready removability of the furnace roof facilitates repairs to the means for supporting the electrodes in the furnace, and is particularly useful where repairs to water jackets and water supplying means for cooling the electrodes become necessary. The use of the described device increases the thermal efliciency of the furnace, since so short a time is required for charging the furnace that less cooling occurs than where a slow charging through small doors is necessary, and because of the fact that the entire charge may be introduced at one time with a consequent reduction in the necessity for opening the furnace door during the treatment of each heat. This latter fact also results in a decrease in the oxidation of the molten metal undergoing treatment.

In the usual practice with the Heroult furnace the post for carrying the door operating mechanism is supported on the fur nace bowl, and projects above the roof of the at furnace. Although no furnace door is illustrated in the drawings, the door operating mechanism may obviously be supported on the furnace roof so that it otters no impediment to the removal of the roof'from the bowl.

Although the present invention is shown as applied to, and is peculiarly adapted for use with, a furnace of the Heroult type, it

will be understood that it may be readily so modified as to be adaptable for use with other electric furnaces, and in fact withany metallurgical furnace in which the same problems of charging and cooling are presented. Although the truck supporting the mast structure is shown as arranged to run on ways formed by a T-rail and thrust rail, and to be actuated by means of an axle motor. it will be understood that any suitable form and arrangement of ways and actuating mechanism may be employed without departing from the spirit of the invention. F or instance, the truck carrying the mast structure may be moved by means of a suitably actuated rack and pinion mechanism, a suitably arranged drum mechanism, or a number of similar equivalents. A number of further obvious modifications may also be made in the structure and arrangement of the apparatus without departing from the scope of the invention as defined in the appended claims.

'What I claim is 1. In a metallurgical furnace the combination of a tilting bowl, movable means rranged to tilt with said bowl, and a fur- .iace roof secured to said movable means.

2. In a metallurgical furnace the combination of a tilting bowl, a truck mounted on ways adjacent said bowl and arranged to tilt therewith, a furnace roof, and means on said truck to which said roof is secured.

3. In a metallurgical furnace the combination of a furnace bowl, a truck movable on vertically inclined ways adjacent said bowl, a furnace roof, and means on said truck to which said roof is secured.

4. In a metallurgical furnace the combination of a tilting bowl, movable means arranged to tilt therewith, a furnace roof secured to said means and arranged to be removed thereby, and means for securing said roof removing means to said bowl against movement relative thereto.

5. In a metallurgical furnace the combination of a tilting bowl, a roof arranged to cover said bowl, and roof removing means movable on vertically inclined ways adjacent said bowl and to which said roof is rigidly secured.

' 6. Ina metallurgical furnace the combination of a furnace bowl, a roof arranged to cover said bowl, roof removing means horizontally and vertically movable relatively to said bowl and to which said roof is rigidly secured, and means for securing said roof removing means to said bowl against movement relative thereto.

7. In a metallurgical furnace the combination of a furnace bowl, masts adjacent said bowl and arranged to be horizontally and vertically movable relatively to said bowl, a furnace roof secured to said masts, and means for securing said masts to said bowl against movement relative thereto.

8. In a metallurgical furnace the combination of a tilting bowl, masts mounted for horizontal and vertical movement relative to said bowl and arranged to tilt therewith, a roof secured to said masts, and means for securing said masts to said bowl against movement relative thereto.

9. In an electric furnace the combination of a furnace bowl, electrode supporting means adjacent said bowl, means whereby said electrode supporting means may be movedrelatively to said bowl, and a furnace roof secured to said electrode supporting means.

10. In an electric furnace the combination of a furnace bowl, electrode supporting masts adjacent said bowl, means'whereby said masts may be moved horizontally and vertically relatively to said bowl, and a furnace roof rigidly secured to said masts.

11. In an electric furnace the combination of a tilting bowl, electrode supporting means arranged to tilt with said bowl, means whereby said electrode supporting means may be moved relatively to said bowl, a furnace roof secured to said electrode supporting means, and means for securing said electrode supporting means to said bowl against movement relative thereto.

12. In an electric furnace the combination of a tilting bowl, electrode supporting masts arranged to tilt with said bowl, means whereby said masts may be moved horizontally and vertically relatively to said bowl, a furnace roof rigidly secured to said masts, and means for securing said masts to said bowl against movement relative thereto.

13. In an electric furnace the combination of a furnace bowl, electrode supporting means mounted for horizontal movement relative to said bowl, afurnace roof, a connection between said furnace roof and said electrode supporting means, and means comprising said electrode supporting means for raising said furnace roof from said bowl and removing it from position thereabove.

14. In an electric furnace the combination of a tilting bowl, electrode supporting means mounted for horizontal movement relative to said bowl and arranged to tilt therewitli, a furnace roof, connection between said furnace roof and said electrode supporting means, and means comprising said electrode supporting means for raising said furnace roof from said bowl and removing it from position thereabove.

15. In an electric furnace the combination of a tilting bowl, electrode supporting means mounted for horizontal movement relative to said bowl and arranged to tilt therewith,

-a furnace roof, connection between said furnace roofand said electrode supporting means, means comprising said electrode supporting means for raising said furnace roof from said bowl and removing it from position thereabove, and means for securing said electrode supporting means to said bowl against movement relative thereto.

16. In an electric furnace the combination of a tilting bowl, ways arranged to tilt with said bowl, electrode supporting masts mounted on said ways for horizontal movement relative to said bowl, a furnace roof, connection between said furnace roof and electrode supporting masts, and means comprising said masts and said ways for raising said furnace roof from said bowl and removing 1t from position thereabove.

In testimony whereof, I have hereunto set my hand. I

' WILLIAM BUHL. Witnesses:

WALTER S. KLEMANS; SUE B. FRITZ. 

